Geeks To Go is a helpful hub, where thousands of volunteer geeks quickly serve friendly answers and support. Check out the forums and get free advice from the experts. Register now to gain access to all of our features, it's FREE and only takes one minute. Once registered and logged in, you will be able to create topics, post replies to existing threads, give reputation to your fellow members, get your own private messenger, post status updates, manage your profile and so much more.

HaraMo

Posted 28 December 2014 - 01:03 PM

The charger doesn't charge anymore. The laptop kept working until the battery was empty.

It seems the power jack connector in the laptop is damaged (measured that no 19 V was passed to the motherboard and the connector was damaged)

So I bought a new DC in cable. Laptop is disassembled, Now I try to turn on the laptop before I put everything back in its place.

But the led on the new connector doesn't light on if I connect it to the charger that is plugged in in a wall outlet.

If I connect the new dc in cable to the motherboard and try again : no led lights up.

If I connect back the powerbutton, and then try again: no led lights up and no power if I press the power button.

do I first have to put whole the laptop together before the led of the new connector lights up?

How can I check if the charger is still ok? I wanted to use my universal charger but no one matches the hp pavillion laptop power jack.

I even went to two different shops to buy a other universal charger but very strenge that this type of connector was not available.

Where can I find a universal charger that I can use for different laptops, and hp pavillion has to be one of them?

this is what I did:

If I connect the new DC in cable to the motherboard and connect it with the ac/dc power adapter.

I measured the V on the ac/dc power adapter: 19,3V

I measured the V on the motherbord after I connected the new DC in cable, (see image nr 1)

19,3 V (1+2)
18,3 V (1+3)
14.4 V (1+4)

1 = the pin at the red cable.

Image nr 1:

Then I measured the V a little bit further on the motherboard (see image nr 2)
If I change the multimeter to the symbol with the arrow,
I can make the led light up, only if the black and red part of the multimeter are touching the motherboard in a certain order.

Image nr 2:

0: down 10.98 V (orange led lights up )
up 11.03 V

3: down 6.49 V
up nothing

0(2): down 5 V
up 5 V (orange led lights up but not so strong as in 0 ).

P03: 0,541 V

P015: down 6.49 V
up nothing

PR150: down 11,02 V (white led lights up)
up 10,98 V

P014: down 5,3 V (white led light up)
up 5 V

But why doesn't the led light up if I just connect the AC.DC power adapter in it?

Why does the laptop doesnt turn on If I connect the power button and press on it? Knowing that the laptop worked great when the battery still worked.

HaraMo

Posted 29 December 2014 - 02:12 PM

zep516

Posted 29 December 2014 - 02:51 PM

zep516

Trusted Helper

Malware Removal

6,981 posts

I did not know that you had the original adapter, connect the adapter up, then get a pencil with a good eraser on it. Gently using the eraser end of the pencil apply pressure to the motherboard so the board flexes a bit, see if the light comes on..

HaraMo

Posted 31 December 2014 - 04:15 PM

HaraMo

Member

Topic Starter

Member

341 posts

I tried it but without pencil with eraser., but no light.

I think it's the adapter itself. I opened another HP (other model G62) connected my universal ac/dc adapter on it, no lights go on, and yet I measure Voltage with the multimeter. Then I changed the ac/dc adapter with the original one: light led up.

It seems the universal had the same wattage (90W) as the original, but the universal has a les Ampere then the original.

Could it be that the laptop I made this thread for is ok, but I need to test it with another ac/dc adapter, to see it this will solve it.

HaraMo

Posted 04 January 2015 - 04:12 AM

Plastic Nev

Posted 04 January 2015 - 11:40 AM

Plastic Nev

Member

Member

485 posts

Hi, there may well be expensive equipment available to a major repair shop, however an ordinary multimeter checking voltages can only go so far, and without knowing what voltages should be present on each part is a bit of a head banging exercise, meaning you are going nowhere.

From the information you have given, I actually suspect there is a major fault on the power management part of the motherboard which can only be proved by a swap of the power board, if a separate one, or if not a complete new mother board.

Considering the power supply itself shows the correct 19 volts, I doubt it is that, though that can be proved on a different laptop. (Most work with the 19 volts units)

zep516

Posted 04 January 2015 - 01:08 PM

zep516

Trusted Helper

Malware Removal

6,981 posts

Agreed, and if you do find a voltage that seems incorrect by whatever reference you're using in determining what the voltage should be. How would you fix it ? It would or may come down to tracing it to a chip, resistor, capacitor, or other component on the board and that's going to be way beyond the skill of most users and likely more damage can occur.

I am a trained electronics technician,

but never had experience on Laptops directly, that being said, I know my limits, I've opened them before and with out direct experience or some training I back away form them in a situation like yours and take it to a shop, whose most likely seen the issue before and no where to tinker, and have spare parts so they can change suspected bad parts and see what the results are.....

Plastic Nev

Posted 01 February 2015 - 06:15 AM

Plastic Nev

Member

Member

485 posts

Hi thanks for the feedback HaraMo, if a motherboard change sorted the problem it is as suspected the power management part faulty. Like zep516 (Joe) I also trained in industrial electronics, however modern motherboard technology isn't made to be repaired when components go dead.